1. Field of the Invention
The present invention relates generally to life jackets and other personal flotation devices (xe2x80x9cPFDsxe2x80x9d), and in particular to the prevention of airway submersion as a novel addition to the classic approach which is to recover the victim after they fall forward onto their face submerging their airway. Concurrently the instant invention continues to improve traditional face down corrective turning action. Central to the prevention of airway submersion is the separation of the centers of ballast and buoyancy. This not only creates increased torque around the axis of rotation that parallels the spine, but because of the anterior posterior separation creates a new axis of rotation around an axis that passes side to side through the thorax. Further improvements in controlling movement of the head, side to side, reduces the amount of torque required for reliable corrective turning action. This results in either decreased bulk of the buoyant moment or the amount of fluid or solid ballast needed to achieve improved airway protection for either inflatable or inherently buoyant personal flotation devices. With increasing concern about passive aspiration leading to drowning while face up in a mounting sea state the current embodiment includes oral nasal airway protection. Due to the morbidity and mortality of rapid onset hypothermia immediate removal from cold water requires inclusion of a personal raft within the PFD that incorporates rapid inflation, and stability in choppy seas and means to survive until rescued. The present invention also provides a garment integrated multi-chambered personal flotation device, life jacket, and the like.
2. Description of the Prior Art
Extensive pool and wave tank testing of fielded and prototype personal flotation devices (xe2x80x9cPFDsxe2x80x9d) on divergent body types indicates the clear need for continued improvement in airway protective performance. None of the jackets tested at several joint international efforts reviewing testing methodologies provided 5-second recovery of the test subjects.
Corrective turning as assessed by every government agency has been restricted to the tester assuming a horizontal face down position taking three strokes, then the administrator assess whether the individual is rolled into a face up position within 5 seconds. Past PFD designs relied upon the common understanding and practice of placing the PFD""s buoyancy high on the chest. All current PFDs tested by the author fail to provide airway protection. There have been PFD recalls and refusal to grant reciprocal approval to product already in the field based on current concerns of the inadequacy of test methodologies. Some agencies instruct their test subjects to place the arms at the sides, legs together and stretch out the back as a simulation of unconsciousness. This methodology was introduced to allow comfortable recreational life jackets to be approved. The use of this methodology for approval of commercial open ocean life jackets has precipitated the global current crisis, with agencies from one country recalling product from another country. The United States Coast Guard (xe2x80x9cUSCGxe2x80x9d) is currently increasing the rigor of testing by the inclusion of new tests more accurately assessing the capacity to commercial jackets to roll an unconscious victim from any position into an airway protected position within 5 seconds as mandated by the Code of Federal Regulations. The current challenge to improve the accuracy of testing is seriously compounded by a lack of PFDs capable of withstanding close scrutiny.
Recent joint Canadian and US wave tank testing of a international selection of xe2x80x9csafety of life at seaxe2x80x9d (xe2x80x9cSOLASxe2x80x9d) class PFDs disclosed that the ability of any life jacket to provide surface airway protection is constrained by the same laws of physics. Even if one is turned face up in mounting seas at very low wave height and frequency the face is awash in waves. As the seas mount, the ballast of the body is driven down in the trough of the wave and the head completely submerged. The buoyant means about the neck if secure extracts the victim in a cyclic plunging action. Thus safety and survival at sea is dependent upon being able to immediately remove oneself from the sea as quickly as possible to avoid hypothermic induced unconsciousness and cumulative aspiration secondary to splashing waves or total submersion that occurs in even relatively mild seas.
The vast majority if not all current jackets fail to turn an unconscious victim who enters the water face first, but since face first water entry is not part of any PFD evaluation program this finding remains unknown therefore unaddressed. Current life jackets also possess a Danger Zone, defined as the vertical position in the water from which if the wearer passes out they then fall face forward into an airway submerged moment of stability. Until now the sole management of the Danger Zone was avoidance. The average user of PFDs is ignorant of the consequence of floating in the danger zone. In fact contrary to the lethal consequences of floating upright in the water column it feels intuitive to the uniformed. The vertical position is the ideal position from which to scan or signal rescue efforts. When you float upright it is easier to monitor the horizon behind you as well as that portion in front of you.
The body has highly developed postural muscles that in coordination with the vestibular apparatus of the inner ear maintain our vertical position in space. Prior jackets relied upon well-established principles that the buoyant moment belonged high on the chest in order to optimize airway protective turning. The prior art has relied strictly upon the use of buoyant means to generate the torque needed for turning and like a sail boat that had lost it""s lead keel the purely buoyant PFD suffered from a lack of orientation, that is there are points of stability that are facedown as well as face up. Hence the urgent need to identify and remedy the Danger Zone.
The prior art is restricted to very severe limits on the angle of flotation of the body off of vertical as one means to avoid entering the Danger Zone. That is if a jacket floats the wearer closer than 20 to 30 degrees off of vertical it would not pass testing and would not be approved for use. At issue is that prior Life Jackets allow the center of gravity of the jacket to be balanced above the center of buoyancy by the conscious wearer floating upright in the water column as they want to be when eagerly trying to spot search and rescue efforts. The intuitive element is that if a PFD allows the center of gravity to be located directly above the centroid of buoyancy the system is in balance and so requires very little muscular movement to maintain this position in gravity. However, the problem occurs as the water environment quickly wicks away the body""s heat leading to hypothermia, obtundation and eventually loss of consciousness. Upon loss of consciousness the victim can no longer maintain their vertical position in space, they can not even hold their head erect. The debility is so complete they cannot remove their face from the water.
Reviewing the mechanics of the Danger Zone, while conscious the victim can effortlessly balance themselves upright but when the head drops forward the center of gravity suddenly also shifts forward, and the individual slumps face down.
The entire global PFD community currently accepts the SOLAS standard for turning. A SOLAS Approved Life Jacket will roll an unconscious victim from any position into and airway protected position within 5 seconds. However that same community relies some variation of the Three-Stroke Test to confirm performance to that standard. PFD design has come to rely upon the assistance provided by the tester to the serious detriment of performance. One current test methodology simulates unconsciousness by instructing the tester to take three strokes, pull the arms to the sides, place the legs together, straighten the back then drop the head. This very complex maneuver aligns the body along the axis of rotation reducing the amount of torque the Life Jacket needs to generate in order to roll the victim over. The majority of the torque is generated from the water displaced by the buoyant moment. While the Three-Stroke test arose to facilitate the creation of comfortable recreational PFDs that same test replaced more passive simulations of unconsciousness. Clearly that more passive tester requires a Life Jacket of greater torque to perform corrective turning.
Both the commercial and recreational market place is currently full of Life Jackets that rely upon tester participation to compensate for insufficient torque. While these comfortable jackets take up less space aboard vessels allowing for the carriage of more passengers they fail the unconscious user. When the head drops forward shifting the center of gravity in front of the center of buoyancy the unconscious users slowly rocks forward covering their airway with water. An accurate simulation of loss of consciousness involves the production of minimal or ideally no kinetic energy. Under current efforts to review validity of current three stroke test methodologies, newer static tests of currently fielded Tested and Approved product although low volume, comfortable and stowable, fail to turn them into a face up position within the mandated 5 seconds.
The current standards are the product of a very large committee. 190 countries each advocating the interests of their individual manufactures has led to an assembly of contradictory mandates. For example, one has to be able to swim, while wearing the Life Jacket, a distance that exceeds what the average American is capable of swimming even without a Life Jacket. One needs to be able to climb into a life raft which is very challenging even when the individual is not wearing a PFD. The Life Jacket needs to position the user upon completion of the corrective turn simultaneously within narrow limits for freeboard, head angle, body angle and face plane while not obstructing the view of the horizon. The same comfortable, snug, low profile Life Jacket must be stable in mounting seas. One size needs to be able to fit anyone and the user needs to be able to put it on from either the front or back in less than 1 minute from the first time the user sees it in the dark. This must all be accomplished in a vest that is so comfortable that it will be worn continuously, so small it will fit under the seat and usually sell for $11.00. Consequently, given these requirements, no current PFDs in the field perform to the standard as denoted in the Federal Code of Regulations.
The third party tester is thus charged with determining whether fielded Life Jackets are capable of rolling an unconscious victim floating face down into and airway protected position within 5 seconds. If the jacket allows a balance to be achieved when conscious, when the wearer looses consciousness, the head drops, moving the center of gravity forward and the wearer""s face ends up in the water. At this point the life jacket has the sole responsibility to effect a corrective turning action. Few, if any, fielded life jackets are capable of corrective turning without the assistance of movement on the part of the wearer. Even if a life jacket could reliably turn the unconscious victim into an airway-protected position; the wearer is exposed to airway submersion during the recovery that will result in some degree of aspiration during the corrective turning action. If the amount of aspirated water accumulates to 200 cc the victim moves from near drowning to drowning.
Additionally, the simplest and lightest ballistic vest are made from KEVLAR brand fibers. In addition to the KEVLAR brand fiber vest the individual might place solid armor plates on the front and/or back. Further complicating the airway protection of the heavily armored individual is the divergent range and location of armaments and gear. As the amount of buoyancy is increased simply to keep the soldier or officer afloat the shear size of the buoyant device becomes a source of stability in the face up as well as face down situation.
It is to the effective resolution of the shortcomings of the prior art that the present invention is directed.
The present invention provides a novel PFD that increases the amount of airway protective torque generated by the Life Jacket. Complementing the disclosed separation of the centers of gravity and centers of buoyancy to increase the generated torque are disclosures reducing the amount of torque required by stabilizing the victims head in line with the axis of corrective turning action. The present invention also prevents airway submersion, rather than allowing the victim to fall face first into the water then attempting to recovery the victim within the allotted 5 seconds which is common with conventional PFDs. The creation of an axis of rotation through the waist relies upon moving the ballast posterior and superior while shifting the center of buoyancy down and away from the axis of rotation. This axis pulls the obtunded victim straight back completely avoiding submersion.
The inclusion of ballast in the PFD results in two opposing forces participating in initiation and completion of corrective turning. In one embodiment a solid ballast, such as lead, is used because its high specific gravity allows the smallest diameter sphere per unit mass. The smaller ball can traverse smaller containers, also reducing cost. The smaller contained mobile eccentric ballast occupies less space within the cover of the PFD resulting in the preservation of the amount foam displacement means. In an alternative embodiment, water is introduced into the container, in lieu of solid ballast. The water is quite heavy when in the air and is uniquely neutrally buoyant when under water. The solid ballast is capable of staying near the perimeter where it reinforces the side high position with its reduced freeboard if not out right airway submersion.
The fluid ballast preferably flows over minor imperfections in the container""s inner surface. The relocation of the fluid ballast begins immediately once the victim crosses the inflection point in the corrective turning action. The fluid ballast can relocate on a partial basis, rather than the all or nothing outcome of the solid ballast. While lead shot ballast of small diameter flows similar to a liquid it is not neutral once submerged and may not be reliable in traversing a soft fabric container where water can negotiate and surface with impunity.
The primary goal of the life jacket is to protect the airway upon entrance and during the initial shock that ensues. If trauma occurred prior to entry such as being struck by the boom of a sailboat then face up flotation is critical. If the individual is conscious depending on the water temperature they have sometimes less than an hour to exit the water or suffer a drop in core temperature that will lead to loss of consciousness. The Life Jacket must therefore also carry with it the means to exit the water. Bridging the two chest straps a life raft acts as a cummerbund holding the PFD to user. Once stable the PFD is removed.
The present invention also provides a valise that is securely attached to the life raft so that as the raft kites during inflation it will not blow away across the seas. Assisting this is a wrist lanyard at the opening of a windsock inflation means. The windsock is held aloft till full, then the neck is closed and the entrap air milked into the chambers of the raft either simultaneously or sequentially through the use of different pressure relief valves. Due to the extreme difficulty of controlling a six-foot inflatable in high winds a secondary body lanyard attaches the raft to the victim. If there is no wind the windsock can be shaken to scoop up air and then transfer that air to the raft. This rapid inflation occurs without the use of expensive, heavy, bulky compressed gas and inflation apparatus, which requires frequent maintenance and fears of failure at many points. Additional novel uses of the windsock further improve safety and survival at sea such as filling it with water to serve as a sea ballast, which helps hold the raft to the water""s surface. In the event that the raft overturns on a breaking wave the sea ballast quickly reorients the raft and its victim if securely restrained within the raft.
A quick release cover serves not only to keep the victim aboard if it happens to overturn, but also to protect the victim from sunburn, as well as serve as a means to capture rain or wind as the weather improves. Approximately, one half of the cover can be quickly releasable in the event that the raft does not flip back over, when overturned, to allow the victim to slip out. When the windsock is attached at multiple points, one can preferably be the center of the body where it inflates the floor as well as one or two perimeter points of inflation. Once in the raft the windsock opening can be closed converting it into a sea ballast bag. A fill tube accessible to the raft""s occupant allows the ballast bag to be filled. The ballast fuses the raft to the water""s surface and supplies a massive keel in the event of broach.
If the seas are not breaking, the windsock can be detached and the reinforced perimeter attached at three points identified by grommets to allow the windsock to serve as a steering sea anchor orienting the raft in the waves. Once the storm is over the windsock with reinforced receiving pouch and lash cord can be attached to a paddle handle and serve as a spinnaker or sail as the victim attempts to move towards shipping lanes to improve chances of rescue. The windsock can be constructed from waterproof coated fabric and can also serve as a funnel to collect and store rain water. If the windsocks inner face is black or dark the inclusion of a piece of clear plastic allows the construction of a solar still capable of capturing potable condensate.
Thus, the invention provides for a fluid ballast, alone or in combination with a solid ballast means, that is functionally directed to different locations within the boater""s personal flotation device or diver""s Buoyancy Compensator BC through a rigid or flexible container. Complementing the effect of the shifting ballast on the PFD""s airway protective turning action is the torque generated by the structurally enhanced buoyant means. The invention allows both the amount of ballast and buoyancy needed to effect reliable face flotation to be reduced to their minimum by a disclosed inverted configuration of the buoyant moment. Shifting the center of buoyancy away from the axis of rotation creates a longer arm and thus more torque per unit of displacement. Further the inverted configuration results in the buoyant force acting through the apex of its triangular configuration creating a hinge which confers flexibility. That flexibility allows the buoyant moment to shift off to the side thereby helping to initiate turning.
The size of the connection between the inferior anterior buoyant means and the posterior superior cervical ballast allows escape of the submerged buoyant means to initiate turning. If the apex is overly narrow without the buoyant means moves without control, dissipating the energy needed for rotating the victim""s face out of the water. The apical joint also flexes about the thorax increasing comfort. In addition the triangular configuration establishes an open space to allow unimpeded arm movement during swimming as required for PFD approval.
The integration of ballast and buoyant moments into a continuous structural base layer improves transfer of torque from both the fluid/solid ballast and the opposing extended buoyant arm. The particular arrangement disclosed allows the unconscious victim to be pulled straight back thereby avoiding face down flotation rather than first allowing face down flotation then attempting to roll them over onto their back. The prevention of drowning relies upon a new described turning action about an axis through the waist. The disclosed product because of its combined use of dual arms demonstrates marked improvement in classic rotation about the spine previously the only identified or assessed corrective turning action. The disclosed adjustable cervical collar includes a mandibular shelf preventing both anterior posterior movement as well as side to side movement.
Controlling the considerable ballast of the head reduces the amount of torque required of the transpontine ballast and buoyant moments. In current automatically inflated PFD on face first entry, the neck is driven through the jacket opening and product failure consistently occurs. To assist in controlling the head and neck, the present invention provides overlapping and pneumatically compressed locks assist in maintaining necessary control of the heads ballast. Decreased need for torque converts into a smaller PFD leading to increased comfort, compliance and therefore improved utility in preventing drowning. Due to mounting concerns from wave tank tests about drowning while floating face up several novel airway protective devices are disclosed that complement the airway protection that arises from either prevention of airway submersion or the rapid recover from the face down position in the event it occurs.
Furthermore, compliance with children is a serious problem, the child""s vest is not only improved functional fluid ballast, its inclusion in a clear tube with brightly colored fish swimming around as the water moves improves the chances of being worn as well as providing enhanced airway protection. Additionally, survival at sea, if one does not immediately drown, is proportional to the rate of heat loss or passive intrusion of water from breaking waves. Disclosed is a rapid manual inflation means for a personal raft stowed within the back of the PFD. After inflation, the means of inflation can be used as a sea anchor to orient the vessel in building seas. In breaking seas the inflation means can be converted to an Icelandic sea ballast to secure the raft to the waters surface. Once the storm had past the detachable inflation means can then be held aloft to function as a sail to move the raft towards shipping lanes to improve chance of rescue. The raft inflation means constructed of coated fabric now acts as a funnel to collect and store rain. If constructed of dark coated fabric and can be combined with a clear cover and now serve as a solar still, dramatically extending the duration of safety and survival at sea from an hour to weeks.
Thus, in one embodiment the invention provides for a fluid ballast, alone or in combination with a solid ballast means, that is functionally directed to different locations within the boater""s personal flotation device (xe2x80x9cPFDxe2x80x9d) or diver""s Buoyancy Compensator BC through a rigid or flexible container. Complementing the effect of the shifting ballast on the PFD""s airway protective turning action is the torque generated by the structurally enhanced buoyant means. The invention allows both the amount of ballast and buoyancy needed to effect reliable face flotation to be reduced to their minimum by a disclosed inverted configuration of the buoyant moment. Shifting the center of buoyancy away from the axis of rotation creates a longer arm and thus more torque per unit of displacement. The invention provides a vertically eccentric PFD, combining inferior and anterior shift in the center of buoyancy with superior posterior shift in the center of gravity, generating torque needed for improved corrective righting action of the PFD.
In another embodiment, the present invention also provides a multi-chambered high torque PFD for powerful corrective turning action of a weighted individual. Disclosed is a multi-chambered device capable of being adjusted to provide a wide range of buoyancy as might be needed under differing degrees of ballistic protection. The disclosed eccentric mobile buoyant system complements the massive displacement required to float the armored victim by providing the energy required to reliably initiate corrective turning action, regardless of the gear worn, position of water entry, or state of consciousness of the wearer. In the event the conscious victim desires to shed the body armor, a series of quick release means allows the victim to shed their ballistics vest while retaining their life jacket.
The individual wearing body armor or heavy equipment on or around the water creates a challenge in the event of sudden entry. In a military setting each strike plate weighs over 9 pounds, typically the individual is also carrying significant armaments, or additional gear. The individual need s not only to float but to be assured that if they injured before suddenly entering the water that an integrated PFD will also orient them into a face up situation. DO to the shear mass attached to their person the buoyant moment attached needs to support the gear as well as the unconscious wearer. As the size of the bladders used to support the armored individual their size creates a secondary problem stability face down as well as face up. Additionally while the use of 9 lbs. of ballast on the back of the victim can augment the corrective Turing action of the integrated life jacket system it is possible that the individual may only have placed a plate on the front of their vest dramatically shifting the centers of ballast and buoyancy. Obviously arrangement of extra ammo, weapons and communication gear may also be of assistance like wise it may also be a detriment to the life jacket system. Further it is desirable that the Life Jacket be able to be activated while wearing the body armor but latter the victim may desire to drop their body armor with out loss of their life vest and thus it is desired that the integrated life jacket upon separation from the heavily ballasted body armor continue to provide reliable airway protection. Currently there are no ballistics vests that provide the unconscious victim with reliable corrective turning action yet alone to consistently provide airway protection under the wide variety of conditions disclosed.